The Effect of Playback Speed and Distractions on the Comprehension of Audio and Audio-Visual Materials

In the modern age, we often consume content at faster than its normal speed. Prior research suggests that watching lecture videos at speeds up to 2x does not significantly affect performance, but the mechanisms by which comprehension is preserved at faster playback speeds are not fully understood. Therefore, we sought to investigate whether there is an effect of speed when the content is audio only, varies in modality (audio-only, audio-visual) and content (textual, pictorial), or is accompanied by distractions. In four experiments, we found that: (1) increasing playback speed to 2.5x speed did not impair test performance (though we still do not advise exceeding 2x speed); (2) having a visual aspect (i.e., presentation slides, instructor images) to learning can be advantageous, especially when processing information at faster speeds; (3) there was a small benefit of receiving textual over pictorial presentations, and the effect did not vary by speed; (4) computer-based distractions (i.e., phone calls, text messages, email notifications) did not impact performance at 1x or 2x speed. Hence, students are more adept at learning at faster speeds than conventional wisdom would suggest, even with distractions present, demonstrating intact comprehension at double the natural speed of to-be-learned material. Furthermore, multimedia presentations can help mitigate the negative costs of accelerated speeds, especially when information is processed by separate working memory components (i.e., narration in the auditory channel, text or pictures in the visual channel), which reduces cognitive load.